Lightning-arrester.



LIGHTNING ARRESTER.

APPLIOATION FILED NOV. 23, 1904.

N 0% 3 L o v N N DU 0 Patented June 13, 1905.

ATENT FFICE.

CHARLES T. MASON, OF SUMTER, SOUTH CAROLINA, ASSIGNOR TO THE SUMTER TELEPHONE MANUFACTURING COMPANY, OF SUMTER, SOUTH CAROLINA, A CORPORATION OF SOUTH CAROLINA.

LIGHTNING -ARRESTER.

SPECIFICATION forming part of Letters Patent No. 792A35, dated June 13, 1905.

Application filed November 23, 1904. Serial No. 233,999.

To all IU7I/077I/ it may concern:

Be it known that I, CHARLns T. MASON, a citizen of the United States, residing at Sumter, county of Sumter, State of South Carolina, have invented certain new and useful Improvements in Lightning-Arresters; and I do hereby declare the following to bea full, clear, and exact description of the inve'ntion, such as will enable others skilled in the art to which it appertains to make and use the same.

The invention relates to lightning-arresters, and has for its object to provide a simple selfcontained apparatus, the parts of which may be readily renewed or replaced, by means of which lightning strokes and other heavy voltage currents maybe diverted from an electric circuit and the instruments and apparatus therein contained.

To this end-the invention comprises a sinuous conductor, preferably in the form of a choke-coil, having terminal connections by means of which the same is included in an electric circuit and an inclosing shell of conducting material with a grounding connection for the same, the conductor and shell being separated from each other by isolated sections of insulating material so disposed that the conductor and the shell are accuratelyspaced apart, but are separated from each other at a multiplicity of points by the atmosphere or other equivalent dielectric, so that the heavy current in its passage along the coil may pass from the conductor through the shell to the ground, and thus be gradually dissipated.

The invention is illustrated in the accompanying drawings, in which Figure 1 is a longitudinal sectional elevation through the complete instrument. Fig. 2 is a transverse section of the same. Fig. 3 is a plan view. Fig. 4 is a longitudinal section showing the shell in elevation. 7

Referring to the several views, (0 indicates a base of insulating material, preferably provided with a central depression. Supported by the base a are two binding-posts c e, to which are connected the ends of a sinuous conductor 0, preferably formed as a choke-coil,

and'said binding-posts c a are adapted to connect the coil 0 in an electric circuit.

Surrounding the coil 0 is a shell I), preferably formed of a hollow cylinder of carbon; but of course said shell may be of any other suitable conducting material and may have any desired form-as, for example, that of a hollow rectangular prism. The shell bis removably secured to the base a by means of spring-clips (Z d, which are secured to the latter, the first by means of a binding-post c, which also serves as a connection for a suitable grounding wire or lead, while the clip cl is fastened to the base a by an ordinary screw 7" or any other suitable means.

The choke-coil c, as will be noted, is disposed in axial alinement with the surrounding shell 6 and is separated from the same by means of isolated sections of insulation, which in the preferred form of the invention consist of longitudinal strips g g, which are spaced at regular intervals between the outer surface of the coil 0 and the inner surface of the shell Z).

These strips g g g are preferably formed of mica, and in addition to their function of spacing the coil 0 within the shell 5 they serve to break the continuity of the air dielectric between the coil and shell, so that the adjacent surfaces of the latter are exposed to each other at a multiplicity of points and a heavy current traversing the coil 0 will jump to the shell I) at the exposed points, and so pass to ground.

If the shell 7; be given the form of a rectangular prism and the coil 0 be made of acorresponding rectangular cross-section, the strips of insulation separating the two will be located between the adjacent flat faces of the coil and shell, leaving the spaces at the corners free, so that a lightning stroke or other heavy current entering the conductor will jump to the shell 7) at these points, and thence be conducted to ground.

It will be noted that my improved arrester as thus constructed consists of a few simple and readily-removable parts and that the arrangement of the coil within the core, while serving to provide a multiplicity of points to carry the current to ground, also serves to protect the coil from the accumulation of dust and obviates the danger of short-circuiting or grounding the coil through the accidental connection of the latter With the shell by means of a fallen wire or other conducting medium.

Having thus described my invention, What I claim is* 1. A liglrtuing-arrester, comprising a sinuous conductor, a grounding-shell of conduct ing material surrounding said conductor, and isolated sections of insulation separating the conductor and shell.

2. A lightning-arrester, comprising a 

